菲律宾蛤仔对扑草净的生物富集与消除规律

Accumulation and Elimination of Prometryn in Ruditapes philippinarum

采用半静态水质接触染毒法,研究菲律宾蛤仔对养殖海水中扑草净的生物富集和消除规律。生物富集实验结果表明:在水温(20±1)℃条件下,在扑草净质量浓度分别为1.0、10.0、200.0μg/L的养殖海水中,菲律宾蛤仔中扑草净残留量随所暴露海水中扑草净质量浓度的升高而逐渐增加,二者之间呈正相关。3个实验组分别在第24、24、6小时达到最大富集值,最大富集系数分别为40.3、9.54、5.35。随着时间的延长,菲律宾蛤仔的扑草净残留量均表现为先迅速上升,升至最高值后迅速降低,低至一定质量浓度后再次上升至一个高点然后下降,之后维持在某一质量浓度水平呈小幅波动的变化趋势。消除实验结果表明:在消除实验初期,3个实验组菲律宾蛤仔中扑草净的残留量均迅速下降,24 h时降至原质量浓度的10%左右,此后下降缓慢,1.0、10.0、200.0μg/L暴露实验组菲律宾蛤仔的扑草净残留量降至10.0 gg/kg以下的时间分别为2、24、768 h,其中1.0μg/L组在消除实验持续96 h时检测结果低于检出限,其余2组在为期45 d的消除实验结束时仍可检出扑草净残留量。研究表明,菲律宾蛤仔对扑草净具有快速富集能力,但完全消除需要较长时间。

The accumulation and elimination of prometryn in Ruditapes philippinarum was studied by the semistatic method.Ruditapes philippinarum were exposed to seawaters containing 1.0,10.0 and 200.0 μg/L prometryn at（20 ± 1） ℃,respectively.The amount of residual prometryn in Ruditapes philippinarum increased with the increase in prometryn concentration.The maximum accumulation of prometryn in Ruditapes philippinarum at the three concentrations was found after exposure for 24,24 and 6 h with bioconcentration factors of 40.3,9.54 and 5.35,respectively.As exposure time increased,prometryn at each concentration could be rapidly accumulated in Ruditapes philippinarum and then reduced,and after another cycle,finally kept fluctuating slightly around a certain level.The amount of residual prometryn in Ruditapes philippinarum from all three concentration groups rapidly dropped during the early stage of elimination,reaching around 10% of the initial level after 24 h,and then fell slowly.The amount of prometryn residue in the 1.0,10.0 and 200.0 μg/L exposure groups was reduced to below 10.0 μg/kg after 2,24 and 768 h,respectively.Moreover,the 1.0 μg/L exposure group reached an undetectable level after 96 h,whereas the two other groups were still detectable after 45 days.This research suggested that Ruditapes philippinarum can accumulate prometryn rapidly,but its complete elimination will take a long time.